What limits do the gospels have as a historical source

The gospels are unique documents, they are not stories based on facts, they are not academic historical documents, they are recounts of personal experiences of several members of a community, they are written to help people to the conversion of faith, for which it is evident the intention and the bias of the writings, is a truthful record of historical facts  

the dominoes began to fall. the surrender at appomattox took place a week later on april 9. while it was the most significant surrender to take place during the civil war, gen. robert e. lee, the confederacy's most respected commander, surrendered only his army of northern virginia to union gen. ulysses s. grant

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